Plan B - So I took the pill after a huge scare, then about 2 and a half weeks later I got what I?

What I thought was my period. It started out as light red spotting, but then by the end of the first day it was a weird, brownish discharge. And the brownish discharge continued for about 4 days. It was completely painless. Which is weird because my cycle is usually pretty heavy and painful. But this time it wasn't. It just ended like 2 days ago. Idk if I should consider that a period or not? Is it normal? Should I be worried? If you've had the same symptoms plz help me!!! ):